The following quotations from D. Seckler, former Director of
the International Water Management Institute (IWMI), are characteristic of
statements by many experts and of the tenor of the discussions at the World
Water Forum held in March 2000:

"For most of modern history, the worlds irrigated
area grew faster than population, but since 1980 the irrigated area per person
has declined and per capita cereal grain production has stagnated. The debate
regarding the worlds capacity to feed a growing population, brought to the
fore in the writings of Malthus two centuries ago, continues. But the growing
scarcity and competition for water add a new element to this debate over food
security. ... In a growing number of countries and regions of the world, water
has become the single most important constraint to increased food
production" (Seckler et al., 1998).

"Many of the most populous countries of the world - China,
India, Pakistan, Mexico, and nearly all of the countries of the Middle East and
North Africa - have literally been having a free ride over the past two or three
decades by depleting their groundwater resources. The penalty of mismanagement
of this valuable resource is now coming due, and it is no exaggeration to say
that the results could be catastrophic for these countries, and given their
importance, for the world as a whole" (Seckler et al.,
1999).

Water scarcity is recognized increasingly as a global concern
and, within that broad concern, more attention is focusing on emerging patterns
of groundwater overexploitation and their implications for the availability of
water to meet human and environmental needs. Food production and food security
are among the more important of these needs. Reliable water supplies,
particularly those from groundwater, are the lead input for increasing yields,
reducing agricultural risk and stabilizing farm incomes. As a result, strong
arguments can be made that access to groundwater plays an instrumental role in
food security.

Water availability and reliability are linked closely to food
security, but the equation linking water to food security is partial and the
links are neither linear nor transparent. The full equation is a function of the
interaction between water access, production economics and the wider network of
entitlements that water users and others have within society. It cannot be
assumed that a one-to-one relationship exists between access to reliable water
supplies for irrigated agriculture and food security (Plate 2).

According to technical documents prepared for the World Food
Summit in 1996, the main generally available indicator of food security is:
"per caput food consumption, measured at the national level by the average
dietary energy supply (DES) in calories on the basis of national food balance
sheets (FBS) and food supplies as national averages" (FAO, 1996). The FAO
definition of food security (above) that this paper follows does not focus on
food production and physical availability alone; it also includes the critical
dimension of access to available food supplies. Under the definition, food
security often depends more on the ability of populations to purchase rather
than produce food. This is because global and national food distribution systems
now frequently negate the impact of local production problems on the
availability of food in the market. As a result, the question of whether people
have access to sufficient food when groundwater problems disrupt agricultural
production depends heavily on whether they have access to a diverse array of
alternative income sources or to reserve capital. It also depends on wider
factors such as transportation systems and the ability of countries to purchase
and distribute food available on global markets. All this implies that analysis
of groundwater availability and reliability on a project or regional basis is by
itselfa poor indicator of the vulnerability of the global population to
food insecurity (Figure 1).

Plate 2 - Pumping in Gujurat,
India. One farmer + one pump = food security - or does it

[M. Moench]

FIGURE 1 - Number of
undernourished in the developing world: observed and projected ranges compared
with the World Food Summit target

Source: The State of Food Insecurity in the World.
FAO, 2002

Nonetheless, access to water, and particularly to highly
reliable groundwater sources, does play an important role in food security in
many cases. Access to reliable sources of water reduces the production risk.
Farm incomes at both micro (farm) and aggregate (regional) levels are buffered
from the effects of precipitation variability, drought or general water scarcity
conditions. As a result, access to reliable groundwater supplies can ensure the
income flow needed to purchase food as well as playing a central role in food
production. Furthermore, particularly in remote locations within developing
countries, irrigated agriculture constitutes the sole source of income that is
available to rural populations. As a result, there can be a direct link between
water access and household or regional food security. However, this link is
highly dependent on the specific situation. There is no inherent direct link
between water and food security. While access to water is important in many
situations, in other situations irrigated agriculture is only one of many income
sources or available livelihood strategies. Consequently, while falling water
levels, irrigation system deterioration, droughts and other direct indicators of
water scarcity can serve as signals that food security may be threatened, the
actual degree of threat will depend on a wide variety of context-specific
factors. Water scarcity measures are warning signals, but they do not on their
own indicate the emergence of food insecurity.

Resource availability and
production

The most direct and tangible link between groundwater
conditions and food security is that of water availability to meet crop
requirements. However, water availability in an aggregate sense has little
meaning as crop production is heavily dependent on seasonal and interannual
fluctuations in availability, including timing in relation to crop growth
stages. Many crops are vulnerable to moisture stress at critical points in plant
growth, and their yields can be reduced substantially even if adequate water
supplies are available following periods of shortage (Perry and Narayanamurthy,
1998). For example, water stress at the flowering stage of maize can reduce
yields by 60 percent even where water is adequate throughout the rest of the
crop season (Seckler and Amarasinghe, 1999). Similar impacts on onions, tomatoes
and rice have also been documented (Meinzen-Dick, 1996). In addition to the
direct impact of water availability on crop growth, assured supplies are a major
factor in inducing investment in other production inputs such as labour,
fertilizers, improved seeds, and pesticides (Seckler and Amarasinghe, 1999;
Kahnert and Levine, 1989). As a result, as the reliability of irrigation water
supplies increases there is multiplier effect on yields. Taken with the inherent
flexibility of groundwater abstraction (on demand, just in time), these
characteristics of groundwater were a major contributor to the role of
irrigation in the green revolution. Irrigated agriculture now contributes almost
40 percent of world food production from 17 percent of cultivated land (United
Nations, 1997).

Expansion of irrigation was the lead input driving
yield increases during the green revolution of the 1960s-70s and subsequent
decades. As the most reliable source of irrigation water, a source that can
generally be tapped when and in the amounts needed, groundwater played a
particularly major role. As Repetto (1994) comments: "The Green Revolution
has often been called a wheat revolution; it might also be called a tubewell
revolution." To this extent, this turnaround hinged upon high-value crops
(with high crop-water budgets) and the ability to pay for energy costs (Plate
3).

Yields in groundwater-irrigated areas are higher (often
double) compared to those in canal-irrigated areas (Shah, 1993; Meinzen-Dick
1996). In India, the groundwater-irrigated area accounts for about 50 percent of
the total irrigated area and up to 80 percent of the countrys total
agricultural production may, in one form or another, be dependent on groundwater
(Dains and Pawar, 1987). Similar patterns are also present in other countries.
In Chinas Henan province, tubewells serve about 2 million ha, or 52
percent of irrigated lands (FAO, 1994). Parts of Mexico, including some of its
most productive agricultural areas, are also heavily dependent on groundwater.
The role of groundwater is equally important in industrialized countries. For
example, Barraque (1998) estimates that: "irrigation uses 80 percent of all
water in Spain and 20 percent of that water comes from underground... The 20
percent, however, produces more than 40 percent of the cumulated economic value
of Spanish crops." Recent findings from Andalusia, Spain, indicate that
groundwater-irrigated agriculture is economically more than five times more
productive (in terms of revenue per cubic metre) and generates more than three
times the employment in comparison with surface-irrigated agriculture
(Hernandez-Mora et al., 1999). The role of groundwater is important not
only through higher yields in normal water years. In an analysis of wheat
cropping in the Negev Desert, Tsur (1990) estimated the stabilization
value (the value associated with the reliability of the water supply as
opposed to just the value of the volume available of groundwater development) as
being "more than twice the benefit due to the increase in water supply".
In southern California, the United States of America, where surface water
supplies are less variable than in the Negev Desert, the stabilization value in
agriculture is as much as 50 percent of the total value of groundwater in some
cases (Tsur, 1993). During the drought in California, the United States of
America, in the early 1990s, economic impacts were minimal largely because
farmers were able to switch from unreliable surface supplies to groundwater
(Gleick and Nash, 1991). The value associated with the flexibility of pumped
groundwater supplies has been a further boost to agricultural productivity as it
has allowed intensification and diversification of agricultural production in
otherwise inflexible surface-irrigation schemes.

However, the presence of groundwater irrigation alone cannot
be given full credit for the increased yields documented around the world. It
needs to be seen as part of a complementary and mutually reinforcing set of
inputs. Groundwater availability has enabled farmers to invest in complementary
inputs that, in combination, have increased crop yields substantially. As FAO
(2002b) notes: "the response of crop to fertilizer is higher where supply of
irrigation water is assured compared to rainfed conditions."It is
the reliability and flexibility of groundwater that allows farmers to take the
risk of investing in fertilizer, but which also substantially increases their
crop productivity. For example, fertilizer use in Pakistan is highest in areas
supplied by both canals and tubewells and thus having a highly assured supply of
irrigation water. The total nutrient application in these areas is 68.85 kg/ha
compared to 29.0 kg/ha in rainfed areas (FAO, 2002b). These observations point
to the dependency of crop yields on interactions within a dynamic agricultural
system and the difficulty of isolating a single factor as the primary factor
contributing to increased production.

Nonetheless, the information available indicates the critical
role groundwater has played in agricultural production over recent decades. The
relationship between assured supplies of irrigation water, increasing yields and
food production is now under stress. According to Rosegrant and Ringler (1999):
"the growth rate in irrigated area declined from 2.16 percent/year during
1967-82 to 1.46 percent in 1982-93. The decline was slower in developing
countries, from 2.04 percent to 1.71 percent annually during the same
periods." Yield increase rates are also declining, and projections indicate
that this will continue in coming decades (Rosegrant and Ringler, 1999; FAO,
2000). Furthermore, in some local areas such as Sri Lanka and in the rice-wheat
systems of India, Nepal, Pakistan and Bangladesh, yields have been stagnant for
a number of years (Amarasinghe et al., 1999; Ladha et al.,
2000).

Although stresses on water resources are increasing and there
is a logical link between water scarcity and yield stagnation, causal
relationships between emerging water problems, yields and food production
vulnerability are not proven. According to Ladha et al. (2000), where
yield stagnation is concerned: "There is some evidence of declining partial
or total factor productivity...The causes for the stagnation or decline are not
well known, and may include changes in biochemical and physical composition of
soil organic matter (SOM), a gradual decline in the supply of soil nutrients
causing nutrient (macro and micro) imbalances due to inappropriate fertilizer
applications, a scarcity of surface water and groundwater as well as poor water
quality (salinity), and the buildup of pests, especially weeds such as Phalaris
minor."

Furthermore, as Seckler and Amarasinghe (1999) note: "It is
very difficult to project crop yields. ... The international dataset does not
distinguish between yields on irrigated and rain-fed area: they are just lumped
together in average yields." Water is only one factor affecting crop yields.
Data available at the global level do not provide much insight into the
relationship between yields on irrigated and rainfed lands, or enable
conclusions about yields on areas irrigated by groundwater or on areas where
groundwater depletion is occurring. Recent evaluations of the implications of
water scarcity for food security range from the optimistic to the pessimistic.
For example, Brown (1999) contends that primarily because of impending water
shortages in northern China, the country will have to import up to 370 million
tonnes of grain per year to feed its population in 2025. This massive increase
in imports could cause steep increases in cereal prices and disruption of the
world market (Seckler et al., 1999). On the other hand, analyses by FAO
and the International Food Policy Research Institute (IFPRI) indicate that yield
increases (rather than increases in cultivated area) will be the dominant factor
underlying growth in cereal production in the coming decades and that, in
aggregate, production increases will be sufficient to meet demand (Rosegrant and
Ringler, 1999; FAO, 2002a). The FAO (2002a) report states that: "The overall
lesson of the historical experience, which is probably also valid for the
future, seems to be that the production system has so far had the capability of
responding flexibly to meet increases in demand within reasonable limits."
(Plate 4).

The core point in this discussion of the direct links between
groundwater availability and food production is the role of interacting dynamic
systems and the uncertainty inherent in predicting outcomes based on partial
understanding of any one of them. The role that irrigation, particularly
groundwater irrigation, has played in increasing yields is relatively clear.
Whether or not emerging water problems are a significant factor underlying the
declining rate of yield increases or represent a significant threat to overall
production levels is less well documented. While the potential nature of such
connections is clear in concept, available data and other evidence are
insufficient to test the conceptual relationships. While it is essential not to
dismiss the implications of groundwater overabstraction and water scarcity for
food production simply because data are insufficient to prove them, it is
equally essential not to ignore the wide range of other factors that could be
playing equal or greater roles. Therefore, the first part of the equation
linking groundwater and food production is clouded even before investigation of
the larger question of the role groundwater plays in entitlements and food
security.

Entitlements and food
security

Food security is a function of three factors: availability;
stability; and the ability of individuals to obtain access to food. As Sen
(1999) and others (Dreze et al., 1995) have argued for famines in India,
starvation is frequently due to the inability of individuals to purchase
supplies that are readily available on the market and is not a function of food
availability per se. The entitlement approach described by Sen "views famines
as economic disasters, not just as food crises."Sen indicates that
the main interest in the entitlement approach probably lies in
"characterizing the nature and causes of the entitlement failures where such
failures occur."

Sens approach may have particular relevance for
analysing the impact of emerging groundwater problems on food security. Studies
in the late 1980s highlighted the critical role that access to water,
particularly groundwater, plays in poverty alleviation (Chambers et al.,
1989). Reliable water supplies are a foundation that enables farmers to afford
access to a wide range of development benefits (from food to education and
health services) and can also enable farmers to diversify into other, often
non-agricultural, income sources. These benefits are accessed through the
improved yields enabled by the green revolution package of inputs. However, they
carry a substantial risk because farmers must make investments in fertilizer,
seed and other inputs in order to achieve them. These investments, which are
often made on credit, will be lost if water supplies fail. Consequently, any
decline in access to groundwater could have a major impact on the economic
condition of small rural farmers. As Burke (2000) argues: "the expansion of
irrigated agriculture in the 20th century has de-coupled the water user from the
inherent risk of exploiting both surface and groundwater resources. The apparent
reliability of storage and conveyance infrastructure and the relative cheapness
and flexibility of groundwater exploitation offered by mechanical drilling have
sheltered the end user from natural hydrological risk."If
substantial groundwater-level declines occur, short-term risk exposure may
return to levels not encountered since the spread of irrigation. This risk is
predominantly economic.

The economic dimension is also central to understanding the
meaning of groundwater overextraction. Most discussions of groundwater
overabstraction emphasize the distinction between economic depletion (i.e.
falling water levels make further extraction uneconomic) and the actual
dewatering of an aquifer. Large-scale aquifers are depleted in an economic sense
(the physical limits to pumping and associated energy costs) long before there
is any real threat of physical depletion. The Gangetic basin may have 6 000 m of
saturated sediment, but only the top 100 m or so are economically accessible for
irrigation. Furthermore, wells owned by small farmers are generally shallow. In
the context of poverty and famine, falling water tables will tend to exclude
those farmers who cannot afford the cost of deepening wells long before they
affect water availability for wealthy farmers and other affluent users (Moench,
1992). Consequently, substantial declines in water levels are particularly
likely to have a major economic impact on farmers with limited land and other
resources. This impact will tend to be particularly pronounced during drought
periods when large numbers of small farmers could simultaneously lose access to
groundwater as their wells dry up. A more creeping problem would occur during
non-drought periods as water-level declines undermined the economic position of
small marginal farmers, forcing them onto already saturated unskilled
agricultural and urban labour markets. The food security crisis in both these
situations would be economic rather than related to foodgrain availability per
se. Furthermore, whether there actually is a food security problem would
depend as much on larger economic conditions (specifically the opportunities
available to farmers transferring out of agriculture into other activities) as
on groundwater availability and the economics of agriculture (Plate
5).

Plate 4 - The physical and
economic limits to pumping, Eritrea

[J.J. Burke]

Plate 5 - Tension between farmers
and municipalit users. Taire, Yemen

[M. Moench]

The question of the larger economic situation is particularly
relevant in the context of global demographic and economic changes. Although the
latest UN assessment indicates a substantial deceleration in world demographic
growth rates, the absolute annual increments in the coming decades will continue
to be large. According to FAO (2000): "seventy-seven million persons are
added to world population every year currently. The number will not have
decreased much by 2015. Even by 2030, annual additions will still be 58
million." Ninety-eight percent of the increase between 1995 and 2020 will
occur in the developing world with the largest absolute growth concentrated in
Asia and the highest relative increases occurring in sub-Saharan Africa
(Pinstrup-Anderson et al., 1999). Population growth will be accompanied
by significant changes in where people live. Historically, rural populations
have dominated those living in urban areas. However, within the next 15 years,
the urban population in developing countries is projected to surpass the rural
population (Pinstrup-Anderson et al., 1999). Furthermore, as populations
urbanize, their aspirations and food-demand characteristics will change. Such
changes are reflected in recent food trade and demand projections. Over the next
20 years, according to Rosegrant and Ringler (1999): "Per capita food
consumption of maize and coarse grains will decline as consumers shift to wheat
and rice, livestock products, fruits and vegetables, and processed foods. The
projected strong growth in meat consumption, in turn, will substantially
increase cereal consumption as animal feed, particularly maize. Growth in cereal
and meat consumption will be much slower in developed countries. These trends
will lead to a strong increase in the importance of developing countries in
global food markets: 82 percent of the projected increase in global cereal
consumption, and nearly 90 percent of the increase in global meat demand between
1993 and 2020 will come from developing countries. Developing Asia will account
for 48 percent of the increase in cereal consumption, and 63 percent of the
increase in meat consumption."

To meet changing demand patterns, FAO and the IFPRI project
substantial increases in world trade for food, particularly cereals and meat
products (FAO, 2000; Rosegrant and Ringler, 1999). Cereal trade is projected to
almost double and meat trade to triple by 2020. To date, traditional cereal
exporters (North America, Australia, Argentina, Thailand, Western Europe and
Viet Nam) have been able to meet sudden rises in demand in developing countries.
However, Brown (1999) points out that grain exports by the principal exporting
countries (accounting for 85 percent of world exports) have levelled off since
1980. There is debate as to whether developing countries will be able to meet
food needs through trade. However, it could also be argued that the high
population growth in some water-stressed developing countries (e.g. Jordan and
Palestinian Authority) shows that food production is not a limit to food
security.

Returning to the question of the link between groundwater
conditions and food security, Sens framework suggests that access to
groundwater will continue to play a critical role in the network of entitlements
that determine food security for rural agricultural populations. However, as
populations migrate from rural to urban areas, direct access to groundwater for
individuals will play less of a role. This is also the case where rural
economies become less dependent on agriculture. Furthermore, the food security
impact of groundwater-level declines on rural agricultural populations will
depend as much on their ability to join the stream of permanent or temporary
migrants to urban areas as on their ability to maintain economic livelihoods in
rural areas. On an anecdotal level, this dynamic is evident in discussions with
farmers in diverse conditions. For example, in many interviews with farmers in
Gujarat, India, concerning groundwater overabstraction and the possibility of
developing management systems, discussions have elicited the following type of
response: "Yes, I know falling water levels will drive me out of production
in a few years, but why should I care? The income I am generating now is
enabling my children to study for an engineering degree; we will not be here in
five years time." Farmers in the United States of America often
express similar sentiments. A young farmer in the San Luis Valley in
Colorado, the United States of America is 65 years old; a wide set of economic
and social factors has induced many young people to prefer a livelihood in the
urban or non-agricultural economy. From a food security perspective, they have
joined the half of the worlds population that depends on global economic,
production and distribution systems within which groundwater availability is
only one element. In this sense, they no longer depend on direct individual
access to local resources such as groundwater.

For urban residents and the increasing population not engaged
in agriculture, food security is likely to become a function of distant
production and distribution systems combined with the economic context
individuals find themselves in. This implies that food security for many will be
influenced at least as much by conditions in the wider economy as by factors
such as groundwater conditions that affect agricultural economics and local
agricultural production per se.

Environmental data and environmental
myth

The discussions above point to the complex nature of the
interactions between groundwater conditions and a large number of factors in the
wider global economic and demographic context that influence food security. Full
analysis of these factors is beyond the scope of this paper. However,
recognition of the complexity and identification of points of leverage within it
is critical to any meaningful analysis of the implications of groundwater
overabstraction for food security. The complexity is also central to identifying
meaningful responses to emerging water problems. Many compelling analyses of
environmental-social relationships have foundered on seemingly minor gaps in
data or system descriptions.

The next section of this paper focuses on groundwater: how
well the resource base and emerging overabstraction problems are understood and,
beyond that, the implications of emerging problems for food production and
security. However, before that, Boxes 1 and 2 present two cautionary examples
that highlight the fundamental risk inherent in posing major global consequences
where there is partial or weak scientific understanding and where the systems
involved are complex.

The cautionary examples in Boxes 1 and 2 contain lessons that
are central to the question of evaluating the impacts of groundwater
overabstraction on food production and food security.

BOX 1: Rain follows the plough

In the last decades of the nineteenth century, throughout the
western United States of America, settlers received land grants of 160 acres
(about 65 ha) under the Homestead Act. The High Plains, an area of rolling
grasslands between the Mississippi River and the Rocky Mountains were a focal
point for settlement. Each year, the waves of settlers drove slightly further
west, claimed land and broke the sod. In one decade, nearly 2 000 000 people
settled on the Great Plains.1

"God speed the plow.... By this wonderful provision, which is
only mans mastery over nature, the clouds are dispensing copious rains...
[the plow] is the instrument which separates civilization from savagery; and
converts a desert into a farm or garden.... To be more concise, rain follows the
plow". (Charles Dana Wilber)2

"Rain Follows the Plow" was a common headline on brochures
promoting settlement. This statement was based on accepted scientific analysis
of the day. Soil beneath the grasslands was rich and often very moist. Ploughing
it would release substantial moisture. According to the theory, as more land was
brought under cultivation, more moisture would be released. This would, in turn,
contribute to cloud formation and ultimately cause rainfall to increase. The
High Plains could be converted into a climate resembling the temperate moist
areas of the east coast. This was science, an integrated theory
grounded on an apparent understanding of the physical processes incorporated in
the model. Furthermore, the climate behaved as predicted. Unusually
heavy rainfall in the 1870s and early 1880s, made the claims sound plausible.
Rainfall in the High Plains appeared to increase as agricultural areas grew. The
story declined as rainfall returned to the lower levels common throughout much
of recent history. The endnote was the Dust Bowl, that great event that reshaped
much of rural America in the 1930s.

Where did the analysis go wrong? First, although the processes
were understood, at least at a gross level, the orders of magnitude on the flows
involved were not. Ploughing may release moisture from the soil, but the amounts
involved were far too small to affect the regional climate. Second, the
model neglected interactions with other systems. Regional and
hemispheric wind patterns are such that any water released from ploughing soil
in the High Plains is often transported huge distances before it reaches the
ground as running water again. Rain did not follow the plough, it only appeared
to.

First, the database relevant to the question being asked was
weak in both cases. This was natural enough in the 1870s-1880s when long-term
rainfall records were unavailable and changes were noted primarily on the basis
of the personal observations of settlers (a situation with many parallels to the
current groundwater debate). However, the database was also weak in the case of
Himalayan deforestation. Despite massive increases in information gathering
technologies, good historical records of forest cover were generally unavailable
and data relevant to critical components of the model, such as suspended
sediment and baseload transport in rivers, remain inadequate to this date. In
many ways, the challenge was one of recognizing that, despite the large amounts
of information available, core data relevant to the questions being asked were
absent.

BOX 2: Himalayan deforestation

One of the most compelling recent environmental stories was
that surrounding deforestation in the Nepal Himalayas. In a classic analysis,
Eckholm (1976) painted a picture of environmental degradation in the hills
having major regional consequences. The model was clear. It
envisioned a direct cause-and-effect relationship between population growth,
mountain deforestation and lowland flooding. "As wood scarcity forces farmers to
burn more dung for fuel, and to apply less to their fields, falling food output
will necessitate the clearing for ever larger, ever steeper tracts of forest -
intensifying the erosion and landslide hazards in the hills, and the siltation
and flooding problems downstream in India and Bangladesh." (Eckholm, 1976). The
interaction between population, food and fuel lay at the heart of deforestation
problems. As forest cover declined, erosion and the speed of runoff increased.
These, in turn, increased sediment loads, caused riverbeds in the Indian plains
to aggrade, and led to increases in flooding throughout the Gangetic basin and
the growth of islands in the Ganges Delta of Bangladesh.

The model was integrated and the database
relatively strong. As Ives and Messerli (1989) stated: "the most compelling and
trend-setting characterization of the Himalayan region and its anticipated
eco-disaster is that published by Erik Eckholm (1975, 1976)...". Forest cover
and flooded areas were being monitored through satellite imagery. Stream gauges
were, at least in some locations, in place and had long-term monitoring records.
Furthermore, as with the conceptual foundations for the rain-follows-the-plough
model, the physical processes were relatively well understood. However, as with
that model, interactions with other systems, in this case plate tectonics and
the expansion of population into marginal agriculture, were ignored or at least
underestimated. As Ives and Messerli pointed out: "The large literature that
depicts the imminence of environmental catastrophe in the Himalayan region has
tended to confuse cause and effect, has largely missed the essential historical
depth, and has assumed the existence of dramatic upstream-downstream
interrelationships without requiring rigorous factual substantiation."
Subsequent research demonstrated that the causal links between many elements in
the model were weak and it was far from clear that forest declines were anywhere
near as widespread as portrayed. Furthermore, even if deforestation was causing
erosion, natural erosion rates related to tectonic uplift were orders of
magnitude higher than the human contribution. Ultimately, the whole basis of
understanding Himalayan deforestation came under question.

"The wide uncertainties that currently exist at the
bio-physical level - uncertainty as to whether the consumption of fuelwood
exceeds or is comfortably within the rate of production, uncertainty as to
whether deforestation is a widespread or localized phenomenon, uncertainty as to
whether it is population pressures or inappropriate institutional arrangements
that lie behind instances of mismanagement of renewable resources ...
uncertainty as to whether deforestation in the hills (if it indeed exists) has
any serious impact on the flooding in the plains - means that a wide range of
mutually contradictory problems are credible." (Thompson et al.,
1986).

In sum, the system and the interactions between systems were
too complex and poorly understood to be captured adequately. Furthermore, the
uncertainty created opportunities for groups in society to advance agendas that
matched their worldviews. The international community made major investments in
reforestation on the basis of the Himalayan deforestation model. It
was practical and pointed to things organizations could do or
invest in in order to solve problems. It not only created a problem
for organizations to remedy but a problem for them to perpetuate as a means of
defining themselves. Ives and Messerli pointed this out: "we must emphasize
again that this uncertainty is not merely technical; that it is not just the
absence of certainty. Rather, it is structural in the sense that, without their
realizing it, certain actors in the Himalayan debate have succeeded in imposing
their desired uncertainties within it." Perceptions of environmental degradation
became so ingrained in the way organizations approached the Himalayan dynamic
that the problems and solutions began to feed on each other. Thompson et
al. saw it as "generated by institutions for institutions. The survival of
an institution rests ultimately upon the credibility it can muster for its idea
of how the world is; for its definition of the problem; for its claim that its
version of the real is self-evident." The model even became a major factor in
arguments by India for the construction of high dams in the Himalayas. These
were portrayed as essential to control floods, the fact that the dams would
produce large amounts of electricity which India wanted and Nepal could sell was
an added benefit.

As the model of Himalayan deforestation has come under
question, the interest of international donors in financing reforestation and
watershed work has waned. Doubts regarding the Eckholm model led
many to question the importance of forestry work in Nepal. However, whether or
not they cause flooding in Bangladesh, forestry problems in Nepal are major and
have a direct effect on the livelihoods of local populations. Linking these
local problems to a regional crisis model may have had short-term
benefits where work on forestry was concerned. However, it may have also
undermined the long-term focus essential to addressing the real local problems
that afflict populations and the forests they depend on in Nepal. This is also a
risk in any model posing groundwater overdraft as a major threat to food
security.

Second, both the cases involved the use of explanatory models
based on a partial understanding of systems. Although accurate, the
physical-process elements underlying the models were partial. As a result, their
predictive value was weak. This is also the case with most groundwater systems.
Models with a strong predictive capacity are unavailable in all except the most
rigorously monitored and analysed aquifers. These aquifers tend to be in wealthy
locations such as the Central Valley of southern California, the United States
of America, and not in developing countries. Furthermore, even rigorous
monitoring and analysis may not enable accurate evaluation of aquifer water
availability. For example, in the San Luis Valley of southern Colorado, the
United States of America, there is a more than 30-percent gap in water balance
estimates despite 40 years of monitoring and analysis driven by litigation over
water availability. Experts believe this gap may be related to deep inflow from
outside the basin or inaccurate estimates of evapotranspiration from native
vegetation, but no one knows for sure. Problems of this type would be
exacerbated under conditions in developing countries where groundwater
monitoring is a relatively new phenomenon.

Third, as with the case of Himalayan deforestation, answers to
the question of the impact of groundwater overabstraction on food security hinge
on complex interactions between water-resource, economic and social systems
(Plate 6). It is unlikely that all three of these systems are understood to a
sufficient degree of precision to develop definitive management responses.
Furthermore, even if the systems were understood, interactions between
non-linear systems often produce unpredictable and counterintuitive results.
This is particularly evident in recent debates regarding the effect of
vegetation on stream flows. In South Asia, re-vegetation of watersheds is widely
advocated as essential for regenerating springs and river flows. However,
studies in Australia document rises in groundwater levels (and the destruction
of pastureland through waterlogging) due to removal of tree cover (Moench,
1998). The effects of vegetation on water availability depend on the delicate
balance between recharge and evapotranspiration. Improvements in soil
characteristics and reductions in runoff associated with vegetative cover
generally enhance recharge. At the same time, the vegetation requires water to
survive, and evapotranspiration increases. Which dominates depends on a wide
variety of factors: species, wind speeds, temperature, soil types, etc.
Significantly different outcomes commonly emerge from subtle interactions
between such factors in local contexts.

All of the above point to the inherent risks in attempts to
link real local problems to global consequences of dubious clarity: it is known
that groundwater overabstraction is a major problem in specific regions. Such
problems have substantial environmental, economic and other consequences whether
or not they have direct implications for global food security. The danger in
focusing on macro food-security concerns is that, if these concerns prove open
to question, attention will be diverted from groundwater problems that are
important in their own right. Furthermore, as in the case of Himalayan
deforestation, approaches designed to respond to global problems
often obscure responses that could be more effective but would only emerge if
the problems were defined in a different way. For example,
approaching groundwater overabstraction from the perspective of global food
security will tend to focus efforts into global and national attempts to manage
the resource base and control use in ways that maintain local and, by
implication, global production. In contrast, if groundwater overabstraction is
viewed as more of a regional concern, then approaches that encourage people to
adapt to scarcity by migrating or transferring out of agriculture (rather than
attempting to maintain production levels) could prove viable.

Plate 6 - Effluent groundwater
seepage maintaining baseflows in Nepal

[M. Moench]

In order to evaluate whether the above cautions
apply to the debate on groundwater overabstraction and food security, Chapter 3
examines the extent to which emerging groundwater problems are understood and
the nature of the available data in key regions.